1. Field of the Invention
The present invention relates to the field of drawer slides of the type used in file cabinets, desks and tool boxes. More precisely the present invention relates to drawer slides that are adapted to prevent the drawer from unintentionally opening.
2. Description of the Prior Art
Drawer slides are designed to function with a minimum amount of friction as a drawer is opened and closed. Such operation allows drawers that are filled with heavy materials to be opened and closed with minimal effort. Unfortunately, this has resulted in a situation where drawers sometimes open when they are not intended to open. This phenomenon is especially prevalent in file cabinet and tool boxes that are designed to be mobile. Specifically, as the cabinet is moved the drawers tend to open. Unintentional and unwanted opening can also occur if the drawer cabinet is not level.
The prior art utilizes several different mechanisms which attempt to address this problem. One such mechanism includes a claw type latch device, constructed from plastic materials, devised to latch onto protrusions in the slide for the purpose of keeping the drawer closed. Another mechanism, designed to prevent drawer rebound, can also have the effect of latching the drawer. Such a device is shown in U.S. Pat. No. 4,932,792. A third mechanism, which utilizes a complex spring cam device designed to prevent drawer rebound, may also have some drawer latching qualities. Such a device is currently sold by Anchor Slide Company of the Netherlands. Each of these structures, however, has problems associated with them with respect to the desirability for using them to address the problem of unintentional drawer opening. These problems include--relatively low resistance to drawer opening, the structures require a large amount of space, the moving latches are subject to wear and breakage and the complex structure adds significantly to assembly and material cost.
There remains a need for a drawer slide that can reliably and economically keep a drawer from unintentionally opening.